Installation of a GREE FreeMatch R32 2-head wall-mounted heat pump in Sainte-Hélène-de-Bagot, MRC des Maskoutains

The unit is outside, the window is inside: why that metre determines the placement

In 1925, Sainte-Hélène-de-Bagot split in two. The village municipality was created following a dispute over electrification, and it took until 1977 for the village and parish to reunite. This is a municipality that had already spent fifty-two years divided over an electricity issue—a precedent that brings a smile when you come to install a unit whose entire file once again hinges on a square metre and on a decision you cannot see.

The project discussed here was determined by the position of a basement window.

The outdoor unit of this GREE FreeMatch R32 wall-mounted heat pump is installed on a steel bracket anchored to the foundation wall, beneath the home's wooden porch—a volume enclosed on three sides, with an access opening in its skirt, above patio slabs. Just over one metre from the unit, in the same wall, is a basement window. The disconnect switch is between them.

It was this window, not the enclosure, that determined the placement.

What the series has already established, and what we are not rewriting

R32 belongs to the A2L class: mildly flammable and denser than air. Our pages have already covered the regulatory mechanics that follow from this, and we refer back to them rather than repeating them here:

• The minimum room area calculated from the system charge, and the fact that it is checked against the final charge after the actual line lengths are known: our Dundee and Varennes pages.
• The A2L detection sensor as a component in its own right—what it does and what it does not replace: our Sainte-Anne-de-Bellevue page.
• The question “is a covered outdoor volume treated as a room?,” raised by our Saint-Théodore-d'Acton page and rephrased without being resolved by the Saint-Damase page.

We will not decide the matter here either, and we are maintaining exactly the same discipline: no threshold, no surface area, and no published ventilation flow rate. The answer belongs in the manual supplied with the unit, the applicable regulations, and with a building professional—not in an installer’s intuition, and even less so in a blog post.

What this photo adds, and what had never been written

Here is the new point, and it can be stated in one sentence:

An enclosure beneath a gallery and a basement are not two volumes. They become a single volume the moment the window opens.

All our previous pages reasoned about a closed outdoor enclosure: a hollow, a low point, a space without wind. Saint-Damase, for example, considered the water, vapour, and wood of the structure above. None examined the case in which this hollow communicates through an opening made in the wall with the occupied space.

Yet this is the most common case imaginable. A basement window in a foundation wall, beneath a gallery, one metre from a condenser: they can be found in half the row houses and village-core homes in Quebec. And the physical reasoning can be stated without any numerical data: a fluid denser than air, in an enclosed space below ground level, does not rise. It occupies the bottom. And if the bottom has an opening that descends toward another low point, it takes that route.

In the same way, and along the same path, the water flows downward. Our Rosemont–La Petite-Patrie page has already stated that a window well is a basin resting against the foundation, often the lowest point of the entire passage. Our Saint-Eustache page has already published the list of what must never be located under a unit, and a basement window is included. We will reopen neither matter.

What we draw from this is a placement method, not a safety rule—because a safety rule, in this case, is not ours to establish:

1. The window is measured before choosing the side, not afterward. It is shown on the technical inspection sketch with its position, height, and opening type. The sash travel is covered on our Côte Saint-Luc page and is checked with the unit in place, frame open.
2. The unit is placed on the side away from the window, never on the side that brings it closer, even when the line layout would be two metres shorter there.
3. The nature of the space is put in writing in the file, before the first hole is drilled, and decided by the appropriate authority. A contractor who answers, “It's outside, so it doesn't apply,” is answering too quickly—we have already written this in Saint-Damase, and we stand by it.
4. Defrost water is routed outside the enclosure, and never toward the window well. The destination of this water is covered on our Les Cèdres, Ville-Marie, Saint-Eustache, and Ahuntsic-Cartierville pages.

The day the space receives a name

One final point about this enclosure, and it concerns use rather than physics.

In the photo, the space beneath the gallery contains an old mattress, bags, and rolls of synthetic turf. This is not a criticism: it is the normal behavior of a covered, dry space that is invisible from the yard. An enclosure beneath a gallery becomes a storage shed, and a storage shed has no clearance.

The general rule—nothing stored around or beneath the unit—belongs on our Ahuntsic-Cartierville page, and the case of combustible materials near a unit using A2L refrigerant was addressed in Saint-Damase. Here, we add only an observation borrowed from our Ville-Marie page, where it described a rosebush: a unit's clearance almost never disappears by decision. It disappears through neglect. No one thinks, “I'm going to block the air intake.” Someone places a mattress against the wall on a Saturday in October, and the unit lives with it for the rest of its life.

The remedy is administrative rather than technical: in the handover file, the enclosure is identified as a service area, with the clearance to be maintained indicated for each side, and the question asked every year during maintenance—what has been placed here since last year?

Two heads do not mean two rooms—and they do not mean the whole house

The second subject of this project is inside, and it is the one on which expectations most often fall apart.

A two-head system creates two zones. Not two rooms: two zones. And a zone is neither a room nor a floor—it is the volume that an appliance can actually cover with the air it moves.

A closed door is a boundary

The confusion comes from a false intuition: we imagine that a head “heats the house” the way a central system would, pushing air everywhere. That is not what happens.

A wall-mounted head draws in the air from the room where it is located, conditions it, and sends it back into that same room. There is no duct, no return, and no available pressure to push air through a door frame. A corridor is not a duct. Air moves between two open, connected volumes through convection and entrainment, which works reasonably well for an adjacent open-plan area—and hardly at all through a closed door.

The consequence is simple, and you need to understand it before signing: in a home served by two heads, there are almost always rooms that no one serves.

The rooms left out

They are almost always the same:

• The bedrooms at the end of a corridor, with the doors closed at night—that is, precisely when the temperature difference widens.
• The bathroom, small, often on an exterior wall, with the door naturally kept closed.
• The basement, when the head is on the main floor: cold air sinks and warm air rises, which works against you when heating.
• The room above the garage, whose floor is over an unheated space.
• The office or guest bedroom added later, without anyone rethinking the layout.

None of these rooms are “underpowered.” They are simply not in a zone.

What helps, and what does not

We prefer to say it upfront rather than have you discover it later:

• Keeping the doors open works only partially, and only for rooms adjacent to the area. It is not a solution for a bedroom at the end of a corridor.
• A ceiling fan circulates air within a space; it does not move it from one room to another.
• Transfer grilles help equalize two neighboring volumes, provided they are sized and installed by someone who knows what they are doing—and they also carry sound.
• Keeping the existing baseboard heaters in the rooms not served is, in a row house, the most honest and economical answer. The arbitrary “remove everything” approach is addressed on our Saint-Amable, Bois-des-Filion, Boisbriand, Repentigny and Sainte-Thérèse pages, and our position has not changed: a baseboard heater used three weeks a year in a bedroom costs less than the third head that would replace it.

The third head is not an option to check off later

This is the point that must be decided on the day of installation, not two years later.

Adding a zone to an already-operating multi-split system is not a matter of attaching a head to the wall. It requires an available port on the compressor, a line route that does not yet exist, reopening a wall, recovering and recharging the refrigerant—and, with an A2L refrigerant, a new verification of the minimum room-area requirement based on the modified final charge.

Our practice: at the time of quotation, we ask whether a third zone is being considered within five years, and we record in the handover file whether a port remains available and where the line route would run. It costs nothing to write this down today. It is expensive to improvise later. This is the same reasoning applied on our Ville-Marie pages to the electrical service and by Boucherville to the dimensions recorded for the next appliance.

The selected configuration

Three comments.

The 110% oversizing is not a sizing error. With a multi-split system, the heads almost never call for their full capacity at the same time: this is the diversity factor, as established on our Saint-Denis-sur-Richelieu page. A 24,000-BTU head in an open-plan area and a 9,000-BTU head in a bedroom do not demand 33,000 BTUs simultaneously — except during morning temperature recovery, which is precisely when reserve capacity is wanted.

The 24,000 / 9,000 imbalance is the heart of the project, and it illustrates the point above exactly. One large head handles the entire open main floor. One small head handles a bedroom. Two heads, two zones — and the house has more than two rooms. It is written into the quotation, not discovered in February.

No refrigerant was added: at 22 developed metres, we remain well below the factory charge’s 40-metre allowance. The minimum room-size check was nevertheless redone, head by head, using the factory charge.

Mistakes we see on this type of project

• Choosing the side of the unit before surveying the wall openings.
• Directing defrost water toward a window well because it is the natural low point.
• Answering “it’s outside” to a question about confined volume without having the issue resolved.
• Letting an enclosure under a porch become a storage shed without ever identifying it in the project file.
• Selling two heads as though they were a central system. This is the leading cause of dissatisfaction we see, and it is entirely avoidable at the quotation stage.
• Putting off the question of the third zone. Later, it costs three times as much.

Grants and eligibility

The ENERGY STAR-certified GREE FreeMatch R32 systems are generally among the equipment eligible for assistance programs currently available in Quebec. The criteria, amounts, and required documents change from year to year and depend on the heating system already in place — a factor that matters particularly here, since the selected strategy keeps the baseboard heaters in the rooms not served by the heat pump. At AirGreen, we verify eligibility for the project before ordering, and we provide the AHRI numbers and efficiency documentation needed to prepare the application. We do not promise any amount before this verification.

AirGreen in Sainte-Hélène-de-Bagot and the Maskoutains RCM

Sainte-Hélène-de-Bagot has approximately 1,700 residents across just over 71 km², representing a density of about twenty residents per square kilometre, and nearly 740 homes. Its built environment consists of a village core and rural roads, with Principale Street recognized as a heritage interpretation site since 2001 and a church built from 1901 to 1904 according to plans by architect Louis-Zéphirin Gauthier.

The parish was canonically established on February 12, 1853, and proclaimed a civil parish on April 6, 1854 — this is the date the municipality celebrates. The name recalls Helen Shaw, mother of David Shaw Ramsay, owner of the Ramesay seigneury; “Bagot” honours Sir Charles Bagot, Governor General of the Province of Canada from 1841 to 1843. The river crossing the area, the Chibouet, a tributary of the Yamaska, was known to the Abenaki by a name meaning “muddy water.” The municipality’s motto is “Respect, Freedom, Work.”

Highway 20 crosses the area — the village on one side, farmland on the other — and the rest stop at kilometre 152 has made it an important roadside stop since the 1970s. The industrial park is organized around Paul-Lussier Street, named in memory of Paul-Eugène Lussier, a baker who became manager of the local bank branch.

Yesterday, we published an installation article about Saint-Liboire, the neighbouring municipality, and it addressed a completely different issue: a console anchored in a brick wall, the age of the cladding as a quoting consideration, and a side passage shared with a neighbour. If your home is made of masonry and the unit must be mounted on the façade, that is the page to read. This page answers a different question: a unit beneath a gallery, beside an opening, in a home with more rooms than zones.

We regularly work in the area — Saint-Liboire, Saint-Damase, Saint-Hugues, Upton, Sainte-Madeleine, Saint-Hyacinthe — as well as throughout Montérégie, in addition to our regular volume in Montreal, Laval, Longueuil, on the North Shore and the South Shore.

For an assessment in Sainte-Hélène-de-Bagot, whether in the village or along the rural roads, our team comes to your property, checks the openings before choosing a wall, and provides a quote stating which rooms will be served and which will not.